6 Signs You Might Have a Blood Clot

Most of the time, blood clots are a good thing. When you get injured, you need your blood to solidify and clump together at the site to help stop bleeding. But sometimes clots crop up when they're not needed, and that can spell trouble—especially if they form in the deep veins near your muscles. 

"When blood clots form in this deeper system, they can be painful and very dangerous," says Luis Navarro, MD, founder of The Vein Treatment Center in New York City. This kind of clot is called a deep vein thrombosis, or DVT. DVTs are like roadblocks on your blood highway—they cause traffic jams in your circulation and prevent the blood flow that keeps your system up and running.

Things can get even more serious if a DVT breaks away from its original spot and travels to your lungs. Then it becomes a pulmonary embolism, a clot that prevents these vital organs from getting the oxygen and blood they need. That can damage your lungs and other organs and may even be fatal. (Heal your whole body with Rodale's 12-day liver detox for total body health!)

Some people are more prone to a DVT than others, so it's worth staying on top of any risk factors. It's also smart to know the warning signs so you can act quickly. "It's important to recognize symptoms because they can often be minimal or overlooked," and getting prompt treatment is key, says Navarro. Here's what to watch for:

Swelling in One Limb

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Swelling in One Limb

A puffy leg or arm is one of the most common signs of a DVT. "Blood clots can block the healthy flow of blood in the legs, and blood can pool behind the clot causing swelling," says Navarro. It's normal to overlook leg swelling as a symptom of a DVT if you get large or stiff legs when you fly, or during periods of immobility. But be suspicious if your bloated limb comes on quickly, especially if it shows up with a side of pain.

Leg or Arm Pain

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Leg or Arm Pain

Usually, DVT pain comes as a combo with other symptoms like swelling or redness, but sometimes it can be standalone. "Unfortunately, pain from a blood clot can easily be mistaken for a muscle cramp or strain, which is why the issue often goes undiagnosed and is specifically dangerous," says Navarro. DVT pain tends to strike when you're walking or when you flex your foot upward. If you have a charley horse you can't seem to shake—especially if the skin near it is warm or discolored—have your doctor take a look.

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The Skin Near the Affected Area is Warm and Red

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The Skin Near the Affected Area is Warm and Red

While it's true that a bruise is a type of blood clot, it's not the kind you have to worry about. You can't see a DVT. You might see some bruise-like discoloration, but you're more likely to see red. DVTs cause redness in the affected limb, and make your arm or leg feel warm to the touch.

Chest Pain

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Chest Pain

A pain in your chest may make you think heart attack, but it could be a PE. "Both a PE and a heart attack share similar symptoms," says Navarro. However, PE pain tends to be sharp and stabbing, and feels worst when you take a deep breath. Heart attack pain often radiates from upper areas of your body like your shoulders, jaw, or neck. The biggest clue is in your breathing—PE pain is gets steadily worse with every breath you take. Either way, you need help immediately, so call 911.

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Shortness of Breath or Racing Heart

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Shortness of Breath or Racing Heart

A blood clot in your lung slows your O2 flow. When oxygen is low, your heart rate goes high to try to make up for the shortage. Feeling a flutter in your chest and having trouble with deep breaths could be your body sending out an SOS that you've got a PE lurking in your lungs. You might also feel faint, or even pass out. Get help quickly, especially if any of these symptoms come on suddenly.

Unexplained Cough

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Unexplained Cough

Can't stop hacking? If you're also having shortness of breath, high heart rate, or chest pain, it could be a PE. "The cough will be dry, but sometimes people can cough up mucus and/or blood," says Navarro. When in doubt, phone your doc or go straight to the ER.